Set two, last song, Brian Wilson and his band finished-off “Pet Sounds” last night in the Palace Theatre with “Caroline No.” The 1966 Beach Boys album—often named pop music’s greatest accomplishment—was a turning point in Wilson’s writing for the band, his career, and his personal life. Some of its brilliance was Wilson’s deep look into the autumn looming over the permanent summer celebrated in the group’s early material.

“Caroline No” was among a handful of songs from the album in which the good times resonate both musically and lyrically in the growing maturity of Wilson’s persona and the sophistication of the songs that express it.

“Pet Sounds” is a cornerstone of youth culture because it manages, magically, to find more of the sweet in its bittersweet look at growing old.

Last night the song added another level, as Wilson—whose vocal power and ability to sing the falsetto parts is diminished--split the lead vocal with Casey McDonough. He half-spoke the lower parts, deferring to McDonough for the highs.

“Caroline No,” a stark observation of aging, nonetheless was particularly poignant last night, as were “Don’t Talk (Put Your Head On My Shoulder)” and a few more.

The singers’ partnership worked in large part because the songs themselves have the feeling of transition in their emotional tone, which, in a sense, was advanced 51 years since their release to the writer’s relationship with them today.

It helped immensely that they were fabulously interpreted by the 11 musicians backing Wilson. The result of laborious studio work with string sections, odd instruments including the Theremin, finely-tuned harmonies, and Wilson’s own tinkering, the album seems a huge challenge to recreate live.

The performance was surprisingly true to the recordings, streamlining instrumentation when necessary, and retaining the magical feel of “Pet Sounds” as well as possible. That it took at least nine of the backing musicians to sing the harmonies sung by half as many singers on the original recordings, was tribute to the skill of the original members.

The cult of Brian Wilson emerged long after “Pet Sounds” was released and its follow-up, the abandoned would-be-masterpiece “Smile” was recorded. Last night’s performance spoke strongly for its belated honors.

Other late Beach Boys tunes such as “Sail On Sailor” and “Feel Flows” were performed with surprising accuracy by the group, which included original member Al Jardine and later contributor Blondie Chaplin.

While they retained some of their original studio magic, the early hits that dominated the first set were simply a nostalgic tour. The surf and rock-and-roll songs of the early Beach Boys was better served by a band of hungry youngsters.